Diesel engine

Diesel engine, internal combustion engine patented in 1892 by the German engineer Rudolf Diesel (1858–1913). Unlike the gasoline engines used in most modern automobiles, the diesel engine does not ignite the fuel with an outside source of heat such as a spark plug, but uses the heat generated by compression to ignite the fuel-air mixture in its cylinder. To achieve the necessary high temperatures diesel engines must have a high compression ratio. Compression ratios of 16:1 are most commonly used. At this ratio, the temperature within the cylinder reaches 940°F (504°C) and the pressure equals 546 lb (248 kg) per sq inch. (Ordinary gasoline engines have compression ratios between 4:1 and 10:1.)

See also: Diesel, Rudolf.